The present invention is directed towards environmental air conditioning and heating directed to personal use. More specifically, the present invention is directed to apparatuses and methods designed to give individuals the ability to modify their immediate workstation environment to a more desirable comfort level than that established generally in the building.
Modem offices are typically divided into a number of individual workstations with area wide temperature and airflow control. Workstation personnel usually cannot open a window, adjust a thermostat or redirect an air vent to satisfy their individual comfort requirements. This lack of individual comfort control is a constant source of aggravation since occupants usually have different individual comfort levels. This is further compounded by the fact that no matter how well designed a large building is; temperature variations will exist throughout the building thereby adding to the discomfort problem. Addressing individual comfort issues is generally the major complaint item for building managers and, additionally, these comfort issues have been reported as reducing worker productivity by 5-15% (BPAC Engineering, January 2001).
With such a major comfort problem, efforts have been made to provide relief but these approaches have generally required extensive building/workstation modification to accomplish. Personal environmental modules for an individual are known. However, such devices must be directly coupled into the building air duct system to operate. See, for example, U.S. Pat. No. 4,872,397. It is also known to have special ducts distributed throughout modular furniture units, such as partition panels after picking up air directed down from overhead building air ducts. See for example U.S. Pat. No. 5,358,444. The use of xe2x80x9cdouble floorsxe2x80x9d is also known to distribute the primary building air to individual workstations to provide individual control. See, for example, U.S. Pat. No. 5,135,436. These above-identified known approaches are expensive, are targeted towards new construction rather than existing building retrofits, and provide significant restrictions on the ability to reconfigure an existing workspace.
The use of small active heat pump devices at each workstation is also known. See, for example, U.S. Pat. No. 5,499,504. However, in such systems undesirable heat is concurrently produced at the workstation while the cool air is being generated for added workstation air conditioning. Likewise, the converse is true. Undesirable cooling is vented from such devices concurrently with the desired generation of additional heating. This added, undesired heating (or cooling depending on the mode selected) must be transported out of the workstation environment during operation, such as via complex ductwork. This requirement severely limits the usefulness of such devices. In addition, these active heat pump systems offer no means of reducing electrical power consumption during peak electricity usage periods.
In one embodiment, the present invention is directed to flexible and energy conscious apparatuses and methods for providing individuals with a level of control of their personal environment over and above the general control provided by the building air conditioning system.
According to a further embodiment, this invention provides a solution to the problem of individual, variable workstation comfort that involves, preferably, a desk mountable combination of a thermal store with an active heat pump device. This preferred apparatus and system of the present invention is designed so that when cool air is being provided, the associated and resulting xe2x80x9cheatxe2x80x9d produced is contained within the device""s thermal store and released to the environment at a later time, preferably at hours when the workstation is not occupied. In this way, no heat is released to the area proximate to the apparatus, thus maximizing the effect of the cooling provided. In other words, a greatly reduced amount of xe2x80x9cheatxe2x80x9d that is concurrently produced is released to the proximate environment during cooling. Instead, the xe2x80x9cheatxe2x80x9d is directed to and stored in the device""s thermal store, to be released at a later time when the proximate environment is unoccupied, such as, after work hours. Similarly, according to the present invention, when the present inventive apparatus provides desired heated air to the user, the concurrent cooling effect (taking place at the heat pump device) also is not transmitted to the environment during the heating mode when the heated air is produced and directed to a user, but is contained by reducing the enthalpy, or heat content, of the unit""s thermal store, and then xe2x80x9crewarmedxe2x80x9d from the environment at a later time when the workspace is not occupied. In this way, the present invention does not have its desired heating/cooling effect marginalized by the concurrent production of air having an unwanted temperature. The present invention accomplishes such enhanced heating and cooling without implementing additional workspace ductwork or other expensive means of directing away air having an unwanted temperature. As a result, the present apparatus and system achieves the desired personal comfort improvements at low cost and at low power levels, an important factor for cooling during high demand, such as during summer electricity peaks. It also requires no other building infrastructure than a standard electrical receptacle.
In yet a further embodiment, the present invention is directed to an apparatus for conditioning a localized environment comprising a thermal storage reservoir comprising a thermal storage mass. The preferred apparatus further comprises a first heat exchange surface in communication with the thermal storage mass and a second heat exchange surface located proximate to an air stream. The second heat exchanger is in communication with a heat pump device with a voltage applied thereto. The heat pump device is in communication with both heat exchangers and capable of reversibly transferring heat from the first heat exchange surface to the second heat exchange surface. The preferred device has an air-moving device to create the air stream and an air duct in communication with the air moving device to direct air taken from a localized zone to a position proximate to the second heat exchange surface. A controller device is used to select cooling or heating modes and the controller device is in communication with the heat pump device. According to the device of the present invention, instead of releasing the resultant heat that is generated during a cooling mode to the surrounding environs, such heat is not released from the device, but is directed to the thermal storage mass and stored concurrently during the cooling mode. Further, when the device is used to provide heated air to an area, the byproduct cooling effect that is necessarily generated during such a heating mode is not taken from the surrounding environs, but instead, is taken from to the thermal storage mass.
In yet another embodiment, the present invention is directed to a method for modifying a localized zone comprising the steps of maintaining a thermal storage mass in a thermal storage reservoir and contacting a first heat exchange surface to the thermal storage mass. A heat pump device is provided in communication with the first heat exchange surface and a second heat exchange surface is provided in communication with the heat pump device. The second heat exchange surface is exposed to an airway and an airflow is directed into the airway, exposing the airflow to the second heat exchange surface to cool the airflow and produce an amount of byproduct heat in the first heat exchange surface. In this way, substantially all of the byproduct heat is directed to the storage mass and stored therein. The heat may then be released from the storage mass at predetermined times and amounts when cooling is not desired. In a similar fashion, the present invention is directed to a method for heating a local environment similar to the method presented immediately above, except that when heating is desired, byproduct cooling is directed to the storage mass thus reducing the enthalpy of the storage mass. The cool storage mass is then rewarmed (or heat charged) at predetermined times and in predetermined amounts when heating is not desired.